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Zusammenfassung
Die Forschungsfragen sind:
(a) Wer sind die relevanten Akteure auf dem Gebiet der Umweltbildung im Waterberg Distrikt?
(b) Wie sind die Akteure vernetzt und welche Kooperationen existieren?
(c) Welche Bevoelkerungsgruppen partizipieren an den bestehenden Umweltbildungsangeboten?
Die Hypothese ist, dass insbesondere einkommensschwache Schichten der schwarzen Bevölkerung nicht an den Angeboten teilnehmen.
Das Untersuchungsgebiet Waterberg Distrikt in der Limpopo Provinz wird wie viele andere laendlich gepraegte Distrikte in Suedafrika von ungleichen Machtverhaeltnissen, hoher Arbeitslosigkeit und Spaetfolgen der Apartheid bestimmt. Es gibt nur wenige Studien, die die aktuelle Situation der Umweltbildung im Waterberg Distrikt ausreichend
analysieren (Baber, de Klerk und Walker 2003).
Die Arbeit basiert auf der Nutzung mehrerer sozialempirischer Methoden, wie schriftliche und muendliche Befragungen (Interviews) waehrend der Forschungsaufenthalte
zwischen 2009 und 2018/19 sowie Feldbeobachtungen zwischen 1995 und 2018/19 im Untersuchungsgebiet Waterberg Distrikt. Alle in der Forschungsarbeit befragten Akteure (Schulen, Wildtierfarmen, Naturreservate) vermitteln Umweltbildung. Ein einheitliches Konzept der Akteure in der Umweltbildung für den Waterberg Distrikt gab es bisher nicht, hier setzt die Untersuchung an.
Die Diskrepanz zwischen wohlhabenden weißen Landbesitzern und Investoren auf der einen Seite, und den kleineren, armen Gemeinden mit vorwiegend schwarzen Bevoelkerungsgruppen auf der anderen Seite ist für die Region praegend. Weitere Hindernisse für eine Teilnahme an den Umweltbildungsangeboten sind Chancenungleichheit in der
Bildung. Das Potenzial der Umweltbildung für eine nachhaltige Entwicklung des Waterberg Distrikts ist vorhanden und die Arbeit zeigt auf, wie die Arbeit der Akteure gestärkt und Synergien besser genutzt werden können.
Der im Waterberg Distrikt gut etablierte Oekotourismus kann durch bessere Vernetzung mit der Umweltbildung profitieren und somit zum wirtschaftlichen Aufschwung in der Region beitragen. Der Ökotourismus kann sich zukuenftig mit verschiedenen Varianten, wie Natur-, Agro-, Geo-, Biopark- und Wissenschaftstourismus weiter profilieren.
Das Waterberg Biosphaerenreservat spielt nicht nur eine herausragende Rolle in den Raumentwicklungsplaenen der Limpopo Provinz und vor allem im Waterberg Distrikt,
sondern auch im Oekotourismus und in der Umweltbildung. Umwelterbe, Artenvielfalt und oekologisch sensible Gebiete muessen aktiv geschuetzt und verwaltet werden und es
gilt sicherzustellen, dass sie nicht durch andere Aktivitaeten (z.B. Minenprospektionen) beeintraechtigt werden.
Das Waterberg Biosphaerenreservat sollte in seinen originaeren Aufgaben gestaerkt werden, damit die gesamte Bevoelkerung des Distrikts besser integriert wird und vom Biosphaerenreservat profitieren kann. Es liegt vor allem in der Verantwortung der Waterberg Distriktverwaltung, das Biosphaerenreservat zu unterstuetzen und weiterzuentwickeln (vgl. Blaauw 2018). Somit kann es zukuenftig die langfristige Lebensfaehigkeit der einzigartigen Landschaft foerdern, lokale Identitaet und Stolz schaffen und die Abwanderung aus laendlichen Gebieten in die Metropolen verringern. Mithilfe der Nutzung von Synergieeffekten und weitreichenderen Kooperationen werden langfristig auch die Lebensgrundlagen, Einkommen sowie Beschaeftigung der benachteiligten schwarzen Bevölkerungsgruppen in der Region verbessert. Eine Partizipation aller Interessensgruppen und kollektive Entscheidungsfindung, basierend auf wissenschaftlichen Erkenntnissen, wird die Gemeinschaft staerken, um die Bevölkerung auf die globalen Herausforderungen der Zukunft vorzubereiten (vgl. UNESCO 2015)
Pilot sites are currently used to test the performance of bentonite barriers for sealing high-level radioactive waste repositories, but the degree of mineral stability under enhanced thermal conditions remains a topic of debate. This study focuses on the SKB ABM5 experiment, which ran for 5 years (2012 to 2017) and locally reached a maximum temperature of 250 °C. Five bentonites were investigated using XRD with Rietveld refinement, SEM-EDX and by measuring pH, CEC and EC. Samples extracted from bentonite blocks at 0.1, 1, 4 and 7 cm away from the heating pipe showed various stages of alteration related to the horizontal thermal gradient. Bentonites close to the contact with lower CEC values showed smectite alterations in the form of tetrahedral substitution of Si4+ by Al3+ and some octahedral metal substitutions, probably related to ferric/ferrous iron derived from corrosion of the heater during oxidative boiling, with pyrite dissolution and acidity occurring in some bentonite layers. This alteration was furthermore associated with higher amounts of hematite and minor calcite dissolution. However, as none of the bentonites showed any smectite loss and only displayed stronger alterations at the heater–bentonite contact, the sealants are considered to have remained largely intact.
According to a basic model, the formation of the coastal barriers in the southwestern Baltic can be divided into four evolutionary stages which are characterized by different rates of sea-level rise and varying relations between sediment supply and accommodation space. This model is tested using the example of a strandplain of the island Usedom, along with a local sea-level curve that reflects even smaller fluctuations of the water table and a detailed chronostratigraphy based on OSL measurements that allows the correlation of the morphodynamics with specific climatic phases. The resulting evolution scheme generally confirms the basic model but the timing of the stages depends on the inherited relief and has to be adjusted locally. A comparison with barriers from the W and SW Baltic region shows that the development during the past 5000 years was controlled by climate fluctuations which caused minor variations of the rather stable sea level and consequential changes in sediment supply, accommodation space and foredune deposition. Progradation decline can mainly be related to cool and windy climate phases which centered around 4.2, 2.8, 1.1, and 0.3 ka b2k, while increasing progradation correlated with warmer climate around 3.5, 2.0, and 0.9 ka b2k. The climate warming and the increasing sea-level rise in the recent past, however, led to shrinking progradation rates and may indicate a critical point beyond which the main progradation trend of the past turns into erosion.
Climate change has strongly affected mountain forests through an increasing intensity and frequency of disturbances and forest dieback in recent decades. However, given the strong relevance of forest dieback and potential impacts on forest stakeholders and local inhabitants, it is surprising that this research field is seldom investigated to date. Therefore, this study deals with the perception of climate change-related consequences as well as possible silvicultural adaptation strategies for the Bavarian Forest. Since it can be assumed that various forest ecosystem services will be increasingly in demand in the future, participation by all stakeholders is essential. Therefore, a sequential, mixed-method approach (qualitative and quantitative survey) allows developing concrete guidelines and strategies for adaptive management, in which the diverse social demands on forests can be adequately taken into account.
ABSTRACT
The small terrestrial gastropod Vertigo pseudosubstriata Ložek, 1954 is one of the rarest glacial indicator species in the Pleistocene of Central and Eastern Europe. In all, this species has been found at only about 15 sites in Europe. V. pseudosubstriata was initially described as a fossil in Central Europe and was discovered only later alive in Central Asia. With regard to its modern distribution, 25 habitats with V. pseudosubstriata have been examined in Tien Shan and in the central and southern Altai. These findings seem to capture the contemporary distribution of the species and provide information on the boundaries of its ecological requirements. These data are of great significance for the interpretation of the fossil assemblages. Since the few fossil specimens in Europe date from very different glacial periods in the Elsterian, Saalian Complex and Weichselian, it can be concluded that V. pseudosubstriata apparently immigrated in at least three distinct waves. Most of the Pleistocene specimens in eastern Central Europe and Eastern Europe are reported from archaeological sites of the Upper Middle Weichselian (Gravettian), roughly between 33 and 29 ka cal
bp. In this paper, we review all reported modern and fossil occurrences and discuss the species' ecological range.
: Compacted bentonite is currently being considered as a suitable backfill material for sealing
underground repositories for radioactive waste as part of a multi-barrier concept. Although showing
favorable properties for this purpose (swelling capability, low permeability, and high adsorption
capacity), the best choice of material remains unclear. The goal of this study was to examine and
compare the hydration behavior of a Milos (Greek) Ca-bentonite sample (SD80) in two types of
simulated ground water: (i) Opalinus clay pore water, and (ii) a diluted saline cap rock brine using
a confined volume, flow-through reaction cell adapted for in situ monitoring by X-ray diffraction.
Based on wet-cell X-ray diffractometry (XRD) and calculations with the software CALCMIX of the
smectite d(001) reflection, it was possible to quantify the abundance of water layers (WL) in the
interlayer spaces and the amount of non-interlayer water uptake during hydration using the two
types of solutions. This was done by varying WL distributions to fit the CALCMIX-simulated XRD
model to the observed data. Hydrating SD80 bentonite with Opalinus clay pore water resulted
in the formation of a dominant mixture of 3- and 4-WLs. The preservation of ca. 10% 1-WLs and
the apparent disappearance of 2-WLs in this hydrated sample are attributed to small quantities of
interlayer K (ca. 8% of exchangeable cations). The SD80 bentonite of equivalent packing density
that was hydrated in diluted cap rock brine also contained ca. 15% 1-WLs, associated with a slightly
higher concentration of interlayer K. However, this sample showed notable suppression of WL
thickness with 2- and 3-WLs dominating in the steady-state condition. This effect is to be expected for
the higher salt content of the brine but the observed generation of CO2 gas in this experiment, derived
from enhanced dissolution of calcite, may have contributed to the suppression of WL thickness. Based
on a comparison with all published wet-cell bentonite hydration experiments, the ratio of packing
density to the total layer charge of smectite is suggested as a useful proxy for predicting the relative
amounts of interlayer and non-interlayer water incorporated during hydration. Such information is
important for assessing the subsequent rates of chemical transport through the bentonite barrier.
This work scrutinises the policy shift in Germany with the change in leitmotif from biotechnology to bioeconomy and examines the associated implications at various levels. The emergence and implementation of innovation policy funding programmes show that the policy transition did not follow a linear sequence. Neither excessive prioritisation nor neglect of a selected sector can be confirmed in this analysis. However, the policy shift from biotechnology to bioeconomy has not only consequences in terms of its content, but also affects the spatial distribution of R&D funding. Against the background of existing polarisation tendencies and the growing acknowledgement of inclusive innovation policy approaches, this study examines the importance the bioeconomy can assume in the reduction of regional disparities. In ‘organisationally thick’ regions, depending on the involvement of private actors, specialisation and regional branching can be observed. It is found that, for rural regions, the bioeconomy can be an appropriate tool for regional development, since other industries are often not present.
Abstract
We investigated four subaerial (paleo)lacustrine landforms at the north‐eastern shoreline of Schweriner See, north‐eastern Germany. These included two beach ridges, one subaerial nearshore bar and a silting up sequence located close to a fossil cliff, which marks the former maximum extent of Schweriner See. We used luminescence profiling with a SUERC portable OSL device (POSL) on all four sediment sequences in combination with sedimentological investigations such as grain size, loss‐on‐ignition and magnetic susceptibility to provide information on the various formations in a lacustrine depositional environment. The POSL reader was used on pre‐treated polymineral samples to gain an insight into luminescence distribution within the individual sediment sequences, but also among the four sequences. POSL proved valuable to understand depositional processes, which were not visible in lithology or sedimentological parameters. With somewhat larger uncertainty this method provides relative chronologies of the sediment sequences. Additionally, we carried out radiocarbon dating and full optical stimulated luminescence (OSL) dating to establish a chronological framework. OSL ages proved to be more reliable to date beach ridges in this setting than radiocarbon samples, which were severely influenced by sediment reworking. This combined approach of sedimentological analyses, luminescence profiling and absolute age determinations revealed details in depositional processes at Schweriner See which otherwise would have remained undetected. Furthermore, it helped to set these subaerial (paleo)lacustrine landforms in a chronological framework.
Bentonite is currently proposed as a potential backfill material for sealing high-level radioactive waste in underground repositories due to its low hydraulic conductivity, self-sealing ability and high adsorption capability. However, saline pore waters, high temperatures and the influence of microbes may cause mineralogical changes and affect the long-term performance of the bentonite barrier system. In this study, long-term static batch experiments were carried out at 25 °C and 90 °C for one and two years using two different industrial bentonites (SD80 from Greece, B36 from Slovakia) and two types of aqueous solutions, which simulated (a) Opalinus clay pore water with a salinity of 19 g·L−1, and (b) diluted cap rock solution with a salinity of 155 g·L−1. The bentonites were prepared with and without organic substrates to study the microbial community and their potential influence on bentonite mineralogy. Smectite alteration was dominated by metal ion substitutions, changes in layer charge and delamination during water–clay interaction. The degree of smectite alteration and changes in the microbial diversity depended largely on the respective bentonite and the experimental conditions. Thus, the low charged SD80 with 17% tetrahedral charge showed nearly no structural change in either of the aqueous solutions, whereas B36 as a medium charged smectite with 56% tetrahedral charge became more beidellitic with increasing temperature when reacted in the diluted cap rock solution. Based on these experiments, the alteration of the smectite is mainly attributed to the nature of the bentonite, pore water chemistry and temperature. A significant microbial influence on the here analyzed parameters was not observed within the two years of experimentation. However, as the detected genera are known to potentially influence geochemical processes, microbial-driven alteration occurring over longer time periods cannot be ruled out if organic nutrients are available at appropriate concentrations.
Are old regions less attractive? Interregional labour migration in a context of population ageing
(2021)
Abstract
Regional demographic change is often conceptualized as a circular process, where out‐migration continuously worsens conditions of population ageing and shrinkage. Thus, if migration acts as a consequence as well as cause of ageing, migration patterns should be influenced by the age structure of origin and destination regions. This paper analyses individual‐level migration decisions of full‐time employees across 326 German regions between 1997 and 2013 using binary choice models. The results show that individuals are more likely to migrate out of and less likely to migrate towards ageing regions. Moreover, the identified patterns are consistent with age‐selective migration reinforcing ageing processes and polarization of demographic structure.